New US research has found more evidence to suggest that eating a mostly plant-based diet could have benefits for health, finding that the diet is associated with a lower risk of developing heart failure among those with no diagnosed heart disease or heart failure.

Heart failure is a chronic, progressive condition in which the heart muscle is unable to pump enough blood to maintain its workload, and it affects around 6.5 million adults over age 20 in the United States.

Although previous studies have shown that diet can play an important role in increasing or decreasing the risk of atherosclerosis, the slow narrowing of the arteries which can cause heart attacks, most strokes and heart failure, the new study focused specifically on whether diet can influence the development of heart failure among people with no diagnosed heart disease.

For the preliminary research the team used data collected from the Reasons for Geographic and Racial Differences in Stroke (REGARDS), a nationwide observational study of risk factors for stroke in adults 45 years or older sponsored by the National Institutes of Health. 

The study included 15,569 patients without known coronary artery disease or heart failure who were followed for between six to ten years.

The team looked at five different dietary patterns including convenience (red meats, pastas, fried potatoes, fast foods), plant-based (dark, leafy vegetables, fruits, beans, fish), sweets (desserts, breads, sweet breakfast foods, chocolate, candy), Southern (eggs, fried food, organ meats, processed meats, sugar-sweetened beverages), and alcohol/salads (salad dressings, green, leafy vegetables, tomatoes, wine, butter, liquor).

Participants were asked to report on their diets using a food frequency questionnaire, a standard method for classifying diets.

After taking into account age, sex, and race of the participants, and other risk factors, the results showed that participants who ate a plant-based diet most of the time had a 42 percent decreased risk of developing heart failure over the four years of the study, compared to those who ate fewer plant-based foods. 

The four other dietary patterns were not associated with a decreased risk for heart failure. 

Although the study was observational -- which means it can only identify a trend or association not prove cause and effect --  first author of the study Kyla Lara, MD, still advised that, "Eating a diet mostly of dark green leafy plants, fruits, beans, whole grains and fish, while limiting processed meats, saturated fats, trans fats, refined carbohydrates and foods high in added sugars is a heart-healthy lifestyle and may specifically help prevent heart failure if you don't already have it." 

The American Heart Association also recommends a diet that includes a variety of fruits and vegetables, whole grains, low-fat dairy products, poultry, fish, beans, non-tropical vegetable oils, and nuts; and limits intake of sweets, sugar-sweetened beverages, and red meats.

The results were presented at the American Heart Association's Scientific Sessions 2017, taking place November 11 to 15 in Anaheim, California.